Water Erosion Research Articles

Effects of Frozen Layer on Composite Erosion of Snowmelt and Rainfall in the Typical Black Soil of Northeast China

Composite erosion caused by snowmelt and rainfall causes considerable soil loss during spring thawing. However, research on the impact of frozen soil layers (FSL) on composite erosion is lacking. Therefore, indoor simulation experiments were conducted on soil conditions of 0 cm (unfrozen soil, FSLUN) and 3 cm thawing depths to explore the influence of FSL on composite erosion in the black soil region of Northeast China. Three snowmelt runoff (SR) discharges (0.34 L min−1, 0.5 L min−1, and 0.67 L min−1), three rainfall (RF) intensities (80 mm h−1, 120 mm h−1, and 160 mm h−1), and three snowmelt–rainfall interactions (SRI; 0.34 L min−1–80 mm h−1, 0.5 L min−1–120 mm h−1, and 0.67 L min−1–160 mm h−1) were used in this study. The results indicate that FSL advanced the initial erosion times of SR, RF, and SRI by 42.06%, 43.33%, and 45.83%, respectively. FSL increased the soil erosion rate (SER) of SRI by 1.2 (1.0–1.6) times that of unfrozen soil, which was smaller than that of SR (16.3, 5.6–25.0) and RF (1.7, 1.6–1.9), indicating that the interaction had an inhibitory effect on the increase in water erosion in the frozen layer. Under FSL and FSLUN conditions, RF erosion was 1.5–4.1 times and 14.5–24.3 times greater than SR erosion. The SRI erosion was not a simple linear superposition of multiple types of single-phase erosion; it had a significant nonlinear superposition amplification effect (SAE), with SAE of ~100% and ~300% under frozen and unfrozen soil conditions. Flow velocity (0.11 < R2 < 0.68), stream power (0.28 < R2 < 0.88), and energy consumption (0.21 < R2 < 0.87) exhibited significant (p < 0.05) linear relationships with SER in both FSL and FSLUN. The research results deepen our understanding of the composite erosion process during the spring thawing period in the black soil region of Northeast China and provide a basis for the prevention and control of soil erosion in the region.

Ecological Evaluation of Land Resources in the Yangtze River Delta Region by Remote Sensing Observation

The evaluation of land ecological security (LES) evaluates how human activity and land use affect land ecosystems. Its ultimate objective is to provide guidance and assistance for decision making in order to preserve and restore the efficacy and health of terrestrial ecosystems. The assessment model presented in this article is comprehensive and integrates the advantages of both subjective and objective weighting techniques. This study extends the “Pressure–State–Response” (PSR) model to “Driver–Pressure–State-Impact–Response” (DPSIR) and combines it with TOPSISI to determine the weights of each contributing component. Furthermore, the geographical and temporal distribution patterns of regional land ecological security levels were investigated using GIS geostatistical approaches. According to this study, (1) the Yangtze River Delta region’s LES index, with a mean value in the fairly safe range, is generally safe. The year 2019 marks an inflection point for the index, with the highest level of ecological safety on land. The primary element is the modification of environmental policies that are enacted by the government. (2) The LES status is divided into two stages during the course of this study. The Yangtze River Delta region’s LES quickly develops throughout the first stage (2012–2019), which sees a shift in the safety rating from IV to II. The second stage (2019–2023) sees a progressive improvement in the LES index and a shift in the safety category from Class II to Class I. (3) Important variables influencing the geographical distribution of LES in the Yangtze River Delta region include barrier elements, including soil and water erosion areas, flood disaster areas, grain planting areas, urban green covering areas, and effective irrigation areas of farmland.

Environmental Impacts of Mechanized Timber Harvesting in Eucalyptus Plantations in Brazil

The advancement of mechanization in forestry has increased productivity in the forestry sector, bringing positive and negative impacts that require a deeper understanding for sustainable forest management. This study aimed to apply a simplified instrument for assessing damage and environmental impacts in forest harvesting of commercial eucalyptus plantations, using a combination of methodologies. The methodology used combined interaction networks and impact assessment matrices, carrying out field surveys, transposing them to interaction networks and weighting them through assessment matrices, resulting in environmental indices (ES) for prioritizing actions. The study was conducted on a commercial eucalyptus plantation in the municipality of São Pedro, São Paulo, Brazil. The mechanized harvesting of the area consists of the structure of a module with a mobile unit consisting of a harvester and forwarder. The results indicated that wood transport presented the highest ES, both positive and negative. The most significant negative impacts (ES) were the depletion of water resources and erosion, while the positive impacts included regional development and job creation. The most notable changes, positive and negative, were observed in the physical and anthropic environment, with a lesser impact on the biotic environment.

Influence of Water Erosion on Soil Aggregates and Organic Matter in Arable Chernozems: Case Study

Since Chernozems are among the most fertile soils in the world, the study of their degradation is of great interest. However, the microstructure and composition of the soil organic matter (SOM) in eroded Chernozems have not yet been sufficiently studied. We studied the SOM and aggregate states of eroded Chernozems using the example of two catenas with arable Haplic Chernozems in the Kursk region of Russia. In the plow horizons (the part of the soil most susceptible to water erosion), we determined the mean-weighted aggregate diameter (MWD), structure and water stability coefficients (SC and WS; dry and wet sieving, respectively), soil organic carbon (SOC) content, and SOM composition and content (qualitative and quantitative micromorphological analyses, respectively). It was shown that with an increase in the degree of erosion, the content of SOC decreased significantly, according to both chemical and micromorphological methods of evaluation. No significant relationships were found between the degree of erosion and the indicators of the structure (except for WS, which was significantly lower in non-eroded Chernozem than in slightly and moderately eroded soils). With the increasing degree of erosion, the humus state of these soils deteriorates at the microlevel, the intensity of humification decreases, the depth of the appearance of assimilated biogenic aggregates with finely dispersed calcite in the profile increases, the structure is destroyed, lumpy aggregates form, and the proportion of planar voids increases. The downslope transport of the soil solid phase under the impact of erosion is accompanied by the accumulation of the transformation products of carbohydrates, phenolic compounds, and black carbon in the passive pool of SOM in the Chernozems in the lower part of the catena. In the Chernozems located in the transit position of the slope, the composition of SOM is characterized by the predominance of lipids and nitrogen-containing compounds. Our unique results contribute to a deeper understanding of the formation of structure and water resistance in eroded soils.

High-temperature melt-infiltration preparation and erosion behavior of γ-Y2Si2O7 /Y2O3–SiO2–Al2O3 glass coating on porous Si3N4 ceramics

Dense γ-Y2Si2O7/Y2O3–SiO2–Al2O3 glass coatings were prepared on porous Si3N4 ceramics using high-temperature melt-infiltration preparation method to improve their stability in service environments, specifically including water resistance and erosion wear resistance. Evolution of structure and mechanical properties during coating preparation was studied. Damage mechanism in erosion wear process was illustrated by putting the coated samples into a high-speed water flow with quartz particles. Dense double-layer microstructure could be formed when sintering at 1350–1450 °C for 1 h. The proportion of each phase inside the coating material prepared by various sintering temperatures was different, resulting in different elastic modulus and hardness, and ultimately affected the erosion resistance of the coatings. The “plasticity index” (E/H value) of γ-Y2Si2O7/Y2O3–SiO2–Al2O3 glass coating prepared at lower temperature (1350 and 1400 °C) was low, and the erosion failure of the coating was brittleness mode, leading to an obvious decrease on waterproof performance after erosion test. While coating prepared at higher temperature (1450 °C) showed a better erosion resistance. After erosion for 2 h, water absorption of coating surface was changed by only 1.34 %. Micro-morphology of the coating was almost unchanged before and after erosion, maintaining excellent waterproof performance.

Plant litter as a heavy metal migration strategy following application of sewage sludge to subtropical forest soils

The environmental risks of migration of heavy metals (HMs) following applications of sewage sludge (SS) to forest soils are garnering increased attention. Plant litter at the forest floor may modify HM migration pathways through impacts on soil aggregates and water/soil erosion; however, HM migration responses to plant litter are poorly understood. The aim of this study was to determine the effects of plant litter cover on HMs migration, and water and soil erosion following the application of SS to subtropical forest soils. Effects of addition of SS along and SS plus plant litter at 0.75 or 1.5 kg m−2 on the migration of cadmium, chromium, copper, nickel, lead, and zinc in surface runoff, soil interflow, and sediments were quantified across nine simulated rainfall events in a laboratory experiment and following natural intense rain events in a field experiment. Addition of SS elevated HM concentrations in surface runoff by 38.7 to 98.5 %, in soil interflow by 48.3 to 312.5 %, and in sediment by 28.5 to 149.4 %, and increased the production of sediment aggregates <0.05 mm that led to greater cumulative migrations of HMs in surface runoff and sediment; sediment accounted for 89.5 % of HM migrations. Addition of plant litter reduced cumulative migration of HMs by 87.1–97.27 %; however, the higher rate of plant litter led to a decrease in surface runoff and sediment yield, and an increase in soil interflow. Addition of plant litter shifted the main pathway of HM migration from sediment to surface runoff and soil interflow. The potential ecological HM risk index was “low” for each treatment. We found consistency in HM concentrations and migrations via surface runoff between the field and laboratory experiments. Overall, the addition of plant litter with SS mitigated soil erosion and reduced total migration of HMs, resulting in a 88.7–97.3 % decrease in the ecological risk index of the six HMs. We conclude that the addition of plant litter may provide a management strategy for the mitigation of HM risks to environmental safety for the disposal of SS in subtropical forest systems.

Surface Flux Patterns of Nutrient Concentrations and Total Suspended Solids in Western Carpathian Stream within Agricultural, Forest, and Grassland Landscapes

The intricate processes of surface water erosion are vital for ecological systems and river-scale management; yet, understanding them comprehensively remains a challenge. Forested agricultural catchments, especially in the Carpathian region, face significant degradation, potentially leading to inorganic nutrient leaching and total suspended solid (TSS) flux. Continuous rainwater inundation of soils in river valleys exacerbates this issue. Utilizing innovative tools like SWAT+, studies have revealed higher concentrations of inorganic nutrients in main watercourses from flysch catchments, with agricultural use linked to N-NO3− concentrations and pasture use linked to anion P-PO43−. Maintaining detailed records is crucial for researchers comparing data. SWAT+ proves valuable for studying TSS washing out and inorganic nutrient leaching, informing collaborative watershed management policies involving stakeholders from agriculture, conservation, and water management sectors. The insights on nutrient leaching, particularly phosphorus (P) and nitrogen (N), are instrumental for shaping policies targeting nutrient pollution within pasture land use for EU agriculture. These findings can guide policy frameworks focused on sustainable practices, especially for eco-schemes, and encourage collaborative watershed management efforts.

Assessment of Multiple Trace Metal Fluxes in a Semi-Arid Watershed Containing Mine Tailing, Using a Multiple Tool Approach (Zaida Mine, Upper Moulouya Watershed, Morocco)

Few studies have quantified the complex flux of trace metals from mine tailings to rivers through water erosion, especially in the semi-arid region of North Morocco (Zaida mine) where soil erosion is a severe issue. This study applies (i) methods to understand and estimate the complex flux of trace metals from mine tailings to rivers, using the RUSLE model combined with the concentration of trace metals in the soil and additionally (ii) pollution indices and statistical analyses to assess the sediment contamination by Cd, Cu, Pb, and Zn. Our study revealed that the basin has a low erosion rate, with an average of 9.1 t/ha/yr. Moreover, the soil contamination is particularly high at the north of the mine tailings, as prevailing winds disperse particles across the basin. The assessment of the sediments indicated that Pb is the main contaminant, with concentrations exceeding 200 mg/kg specifically downstream of the tailings. This study also identified high a concentration of trace elements 14 km away from the tailings alongside the Moulouya river, due to the specific hydrological transport patterns in the area. This research contributes to a better understanding of the transport and fate of the trace metals in mining areas. It proposes a replicable method that can be applied in other regions to assess the contamination flows and thereby assist water resource management.

A systematic benchmarking framework for future assessments of soil health: An example from Denmark

Based on current evidence and established critical thresholds for soil degradation indicators, it is concerning that over 60–70% of European soils are unhealthy due to unsustainable management and the impact of climate change. Despite European and national efforts to improve soil health, significant gaps remain. The proposal for a Soil Monitoring and Resilience Law, to be implemented by the European Union, seeks to establish a framework for soil monitoring and promote sustainable management practices to achieve healthy soils by 2050. This requires extensive data collection and soil monitoring systems to accurately estimate soil health across Europe, considering the diversity of soil types, climates, and land uses. To establish a framework for soil monitoring, we must understand the site-specific status of soil and the ranges of soil health indicators across specific pedoclimatic regions. In our study, we evaluated the soil status in agricultural areas in Denmark using soil health indicators and a site-specific benchmarking approach. We compiled nationally representative datasets, combining point and model-informed data of soil parameters such as organic carbon content, bulk density, pH, electrical conductivity, clay-to-soil organiccarbon ratio, water erosion, and nitrogen leaching. By categorizing Danish agricultural soils into monitoring units based on textural classes, landscape elements, and wetland types, we calculated benchmarks for these indicators, considering different cropping systems. Our approach provided detailed point-based results and a spatially explicit overview of the status of soil health indicators in Denmark. We identified areas where soil deviates from the benchmarks of different indicators. Such deviations might indicate soil functions operating outside the normal range, posing potential threats to soil health. This proposed framework could support the establishment of a baseline for assessing the directionality of future changes in soil health. Moreover, it is adaptable for implementation by other countries to support assessments of soil health.

Effectiveness of Crop Farmers' Use of Indigenous Knowledge on Land Degradation Control Practices in Imo State, Nigeria

This study analyzed the effectiveness of the crop farmers' use of indigenous knowledge on land degradation control practices in Imo State, Nigeria. A multistage sampling procedure was used to select 180 crop farmers for the study. Data were collected using a structured questionnaire and analyzed using mean, percentages, and multiple regression analysis. Crop farmers perceived zero tillage to help in conserving soil texture (x̄=3.52), replanting of deforested areas enables them to maintain vegetative cover (x̄=3.45), use of organic manure to improve soil's organic matter contents (x̄=3.42) and controlling both water and wind erosions by making ridges (x̄=3.30) and rainwater harvesting (x̄=3.10) as highly effective in controlling soil degradation. Age, marital status, educational level, household size, monthly income, membership of association, extension contact and farm size) They significantly influenced their perceived effectiveness of using indigenous knowledge on land degradation control. The major constraints faced by crop farmers were inadequate funds to practice land degradation control practices (99.44%) and limited availability of farmland (98.31%), poor extension contact (86.44%), poor knowledge and education of land degradation control processes (86.44%), poor government support (81.92%) and poor access to information (75.14%). The study concludes that crop farmers experienced soil degradation and were practicing indigenous land degradation, although some factors constrained them. Therefore, crop farmers should come together to transform their indigenous knowledge and control practices, thereby discussing and looking for the best way to tackle their peculiar land degradation challenges.

Dynamic Replacement of Soil Inorganic Carbon under Water Erosion

The dynamic replacement of soil organic carbon represents a pivotal mechanism through which water erosion modulates soil–atmosphere CO2 fluxes. However, the extent of this dynamic replacement of soil inorganic carbon within this process remains unclear. In our study, we focused on Yuanmou County, China, a prototypical region afflicted by water erosion, as our study area. We leveraged the WaTEM/SEDEM model to quantify the dynamic replacement of soil carbon, accounted for the average annual net change in soil carbon pools, and used isotope tracer techniques to track and measure the process of the coupled carbon–water cycling. This comprehensive approach enabled us to scrutinize the dynamic replacement of soil carbon under water erosion and delineate its ramifications for the carbon cycle. Our findings unveiled that the surface soil carbon reservoir in the Yuanmou area receives an annual replacement of 47,600 ± 12,600 tons following water erosion events. A substantial portion, amounting to 39,700 ± 10,500 tons, stems from the dynamic replacement of soil inorganic carbon facilitated by atmospheric carbon. These results underscore the critical role of the dynamic replacement of soil inorganic carbon in altering the soil–atmosphere CO2 fluxes under water erosion, thereby influencing the carbon cycle dynamics. Consequently, we advocate for the integration of water erosion processes into regional carbon sink assessments to attain a more comprehensive understanding of regional carbon dynamics.

Remote Sensing Thematic Product Generation for Sustainable Development of the Geological Environment

Remote sensing thematic data products are critical for assessing and analyzing geological environments, while efficient generation of thematic products is also highly significant for achieving corresponding sustainable development goals (SDGs). Currently, remote sensing thematic product generation has problems like low levels of automation and efficiency. Addressing these challenges is imperative for advancing sustainable development within the geological environment. This paper aims to address issues related to the generation of geological environment remote sensing thematic products, sorting through the overall process of remote sensing thematic product generation, exploring algorithm encapsulation, combination, and execution under technical methods for container and workflow, and relies on the Spark distributed processing architecture to achieve efficient thematic product generation supported by multiple geological environment data processing models. Finally, taking the three SDGs of SDG6, SDG11, and SDG15 as examples, we achieved the generation of a variety of thematic products such as the interpretation of water body distribution, extraction of urban informal settlements and distribution of water and soil erosion. Meanwhile, we comparatively analyzed the efficiency of thematic product generation on different processing architectures, and the experimental results further verified the feasibility and effectiveness of our proposed solution. This research provides a programme for the automated and intelligent generation of geological environment remote sensing thematic products and effectively assists the construction of sustainable development in the geological environment.

The Estimation of the Amount of Water Erosion at Qalachwalan Basin by Gavrivolic Model

Qalachwalan basin is important agricultural and it is one of the main water resources for Slemani city. The basin contains useful natural resources that are conducive to agricultural development. As the area is a hill country, Gavrilovic model was chosen to get the size and amount of water erosion to determine the erosion risks that the basin is facing. This research was conducted based on Gavrilovic (EPM) model using (RS &amp; GIS) to determine the level, amount, and size of water erosion of Qalachwalan basin. We found out that, through the research, the slopes that are in the direction of the estuaries face water erosion much more due to the form of the basin in its creation, which has many slopes and little vegetation on the cliffs that are a main cause of the speedy runoff. Also, poor planning to confront or reduce the risks of flood which increases the erosions. The erosion estimated based on Gavrilovic model between very weak erosion at less than (100 m3/km2/year) and very strong erosion at (5000 – 20000 m3/km2/year). The basin generally lies in the circle of moderate water erosion at (1230 m3/km2/year). Therefore, for the secondary basins (e.g. Jogasur, Mawakan, and estuary) the erosion based on Gavrilovic model was high consecutively in this way (1720, 2584 and 4356 m3/km2/year). Our results very impotent for local government stockholders to establishment new dams in cliffs areas for agriculture and determine life cycle of these dams in this areas, and find new solution to reduce soil erosions in near future.

Soil hydro-physical variables and crop residues determinate runoff, soil loss, and glyphosate and AMPA concentration in the aqueous phase under simulated rainfall events.

Soil structural degradation and water erosion processes were observed even in no-tillage schemes in the Pampas region. Within these conservation systems, agrochemical application per hectare is one of the highest globally. Thus, this entails a serious risk of water contamination. The objectives of this study were to (1) test the hypothesis that the hydrological dynamics and sediment concentration related to surface runoff were conditioned by soil structure regardless of the presence of maize (Zea mays L.) crop residue and (2) assess the incidence of maize crop residue on glyphosate and aminomethylphosphonic acid (AMPA) concentration in runoff. The soil under study corresponded to Arroyo Dulce Series (Typic Argiudoll silty loam soil). Rain simulations were performed in the laboratory on undisturbed soil samples. Total runoff and infiltration rate were similar between treatments with C(+) and without C(-) maize crop residues (C(+) 1381.40mL and 14.27mm h-1, C(-): 1529.70mL and 21.67mm h-1). The C(-) treatments showed a higher sediment concentration than C(+) (1.58 and 0.42g 100mL-1, respectively). Glyphosate and AMPA average values in runoff were 15.9 and 33.9µg L-1. High variability of the hydro-physical properties and occurrence of soil structure, particularly platy ones, were detected. The hydrological variables were conditioned mainly by the occurrence of platy structures regardless of crop residue presence. Glyphosate concentration was increased in the first runoff event by the presence of corn residues, while AMPA concentrations were higher in the second runoff event in both residue treatments. In this study, maize residue on the soil surface protected the soil from sediment detachment but did not change runoff or infiltration. Thus, the implementation of agricultural management practices that promote vegetative residue cover has shown positive results to erosion.

Soil organic matter components and sesquioxides integrally regulate aggregate stability and size distribution under erosion and deposition conditions in southern China

Water erosion considerably affects the stability and particle size distribution of soil aggregates, but the underlying mechanisms of water erosion remain unclear. To this end, we selected four landscape positions (top-, up-, mid-, and toe-slope) with distinct erosion and deposition characteristics on a typical eroded slope in southern China to conduct experiments- aiming to investigate the main drivers of soil aggregate stability during erosion and deposition processes. Soil samples were collected from 12 sites, and 4 size classes (>2, 2–0.25, 0.25–0.053, and <0.053 mm) of soil aggregates were obtained using the wet sieving method. The composition and stability of the soil aggregates, as well as the contents of organic (organic matter components) and inorganic (iron-aluminum oxides) cementing materials of different particle sizes, were determined. The results indicated that erosion significantly reduced the aggregate stability and the >0.25 mm water-stable aggregate content (WR0.25) (P < 0.05). The mean weight diameter (MWD) and geometric mean diameter (GMD) values of the soil aggregates at the eroding site decreased, and the fractal dimension (FD) increased. Furthermore, erosion markedly reduced the humic acid (HA) and fulvic acid (FA) contents in the bulk soils and soil aggregates, while the HA content showed no obvious difference between the eroding and depositional sites. In addition to the presence of complexed iron/alumina oxides (Fep/Alp), erosion markedly reduced the contents of amorphous (Feo/Alo) and free-form (Fed/Ald) iron/alumina oxides in the bulk soils and size fractions. Moreover, Fed/Ald, Fep and Feo/Alo were present in the microaggregates, while Alp was found in the macroaggregates. Additionally, boosted regression tree (BRT) analysis indicated that FA (36.70 %), Feo (19.00 %), and Ald (12.71 %) were the crucial predictors of soil aggregate stability. These findings further confirm that the organic and inorganic cementing materials in red soils collectively contribute to aggregate stabilization under the impact of erosion. This study facilitates a deeper understanding of the mechanisms governing soil aggregate stability in eroded landscapes, and provides a theoretical basis for biogeochemical cycling processes.

Post‐Fire Sediment Yield From a Central California Watershed: Field Measurements and Validation of the WEPP Model

AbstractIn a warming climate, an intensifying fire regime and higher likelihood of extreme rain are expected to increase watershed sediment yield in many regions. Understanding regional variability in landscape response to fire and post‐fire rainfall is essential for managing water resources and infrastructure. We measured sediment yield resulting from sequential wildfire and extreme rain and flooding in the upper Carmel River watershed (116 km2), on the central California coast, USA, using changes in sediment volume mapped in a reservoir. We determined that the sediment yield after fire and post‐fire flooding was 854–1,100 t/km2/yr, a factor of 3.5–4.6 greater than the long‐term yield from this watershed and more than an order of magnitude greater than during severe drought conditions. In this first large‐scale field validation test of the WEPPcloud/wepppy framework for the Water Erosion Prediction Project (WEPP) model on a burned landscape, WEPP predicted 81%–106% of the measured sediment yield. These findings will facilitate assessing and predicting future fire effects in steep watersheds with a Mediterranean climate and indicate that the increasingly widespread use of WEPP is appropriate for evaluating post‐fire hillslope erosion even across 100‐km2 scales under conditions without debris flows.

Environmental diagnostic of municipality of zinacantepec, Estado de México

In the period 2021‑ 2023, technical tours were conducted as part of the Local Ecological Management of Zinacantepec to carry out the environmental diagnosis of the territory, in which soil degradation is present in the sub‑ b asin of the Tejalpa River while the forest ecosystem in the Zinacantépetl Formation is in a process of feedback according to the General System Theory (GST), that is, recovery with a positive trend in the forest cover. The purpose of this research is to analyze the characteristics of the physical‑ g eographical subsystemin order to determine the environmental conditions in the study area. In order to achieve the specific objectives, a methodology based on the evaluation of the disturbances in the balance of the environmental system was proposed, for which thematic cartography was obtained, as well as the state of evolution of the relief by means of matrices applied in field work. On the other hand, through COMPROBIDES, training sessions and working groups have been held to present multidisciplinary proposals that promote environmental protection based on the results obtained, in which processes of land use change, water erosion, deforestation, greenhouse gas emissions, water pollution and urban location in agricultural areas have been identified. It should be noted that knowledge of the geodynamics of geographic space has contributed to social and public participation for the preservation of natural resources.

Anthropogenic impact on agricultural landscapes of the Akmola region of the Republic of Kazakhstan

The relevance of research topic is confirmed by the presence of environmental problems of steppe land use and the need for its rationalization. The article examines the issues of ecological stability of agrolandscapes of the steppe zone in agricultural circulation and determines environmental and economic damage that occurs when their functioning is disrupted. The goal is to assess the degree of anthropogenic influence when using agricultural landscapes based on the example of the Akmola region. The content of research topic determined the choice of the following methods: historical, logical, statistical, system analysis, graphic modeling. Results - taking into account factors that destabilize the landscape-ecological balance, ecological zoning was carried out in the region, the degree of stability of steppe agricultural landscapes under anthropogenic influence was determined, based on mathematical model of erosion process, intensity of washout was calculated, environmental and economic losses arising in connection with violation were indicated, self-regulation of landscapes, environmental protection (antierosion) measures have been developed. The amount of residual flushing after they are carried out characterizes the effectiveness of reducing the water flows. Conclusions - field agrolandscapes of agricultural enterprises of the Akmola region, specializing in production of crop products, can be classified as anthropogenically disturbed with low degree of environmental stability, which is due to the significant plowing of their territory. One of the main factors of environmental destabilization in steppe agricultural entities is the spread of water erosion on slope arable land, environmental damage from which is confirmed by the loss of soil layer. The proposed measures to support landscape environmental stability can be applied when planning the use of land resources and developing on-farm land management projects.

Evaluating rainfall erosivity on the Tibetan Plateau by integrating high spatiotemporal resolution gridded precipitation and gauge data

High-precision rainfall erosivity mapping is crucial for accurately evaluating regional soil erosion on the Tibetan Plateau (TP) under the backdrop of climate warming and humidification. Although high spatiotemporal resolution gridded precipitation data provides the foundation for rainfall erosivity mapping, the increasing spatial heterogeneity of rainfall with decreasing temporal granularity can lead to greater errors when directly computing rainfall erosivity from gridded precipitation data. In this study, a site-scale conversion coefficient was established so that rainfall erosivity calculated using hourly data can be converted to rainfall erosivity calculated using per-minute data. A revised model was established for calculating the rainfall erosivity based on high-resolution hourly precipitation data from the Third Pole gridded precipitation dataset (TPHiPr). The results revealed a notable underestimation in the original calculation results obtained using the TPHiPr, but strong correlation was observed between the two sets of results. There was a significant improvement in the Nash–Sutcliffe coefficient of efficiency (from −0.39 to 0.80) and the Percent Bias (from −63.95 % to 0.37 %) after model revision. The TPHiPr effectively depict the spatial characteristics of rainfall erosivity on the TP. It accurately reflected the rain shadow area on the northern flank of the Himalayas and the dry-hot valley in the Hengduan Mountains. It also showed high rainfall erosivity values in the tropical rainforest area on the southern flank of the eastern Himalayas. The overall trend of rainfall erosivity has increased on the TP during the period 1981 to 2020, with 65.91 % of the regions exhibiting an increasing trend and 22.25 % showing significant increases, indicating an intensified risk of water erosion. These findings suggest that the 40-year-high spatial resolution rainfall erosivity dataset can provide accurate data support for a quantitative understanding of soil erosion on the TP.

Modelling Current-State N- and P-Fluxes into Surface Waters in Germany

For the first time, the AGRUM model consortium—consisting of the agro-economic model RAUMIS, the water balance model mGROWA, the hydrological nutrient transport models DENUZ, WeKu and MEPhos, and the urban emission model MONERIS—was jointly set up throughout Germany (357,000 km2). This provided a nationwide consistent nutrient model to capture the current status of N and P inputs to surface waters from diffuse sources and urban areas. Diffuse nutrient emissions were quantified in high spatial resolution for the input pathways’ groundwater, drainage runoff, and natural interflow (100 m × 100 m), as well as for water erosion and wash-off (25 m × 25 m). The sum of diffuse nutrient inputs to surface waters is about 385,000 metric tons N/yr and ca. 11,530 metric tons P/yr. Urban emissions were quantified either as point source inputs (wastewater treatment plants, industrial direct dischargers) or at municipality scale for different collection and treatment systems, e.g., rainwater sewers or decentralized treatment plants, and sum up to ca. 95,000 t N/yr and 7500 t P/yr. As modelled, total N and P inputs into surface waters correspond well with observed N and P loads in rivers. The model results represent valuable information for water managers, being responsible for the preparation of management plans for the third management cycle of the EC Water Framework Directive spanning from 2021 to 2027.